1. Field of the Invention
The present invention relates to a cover, and more particularly to a cover fit onto a container with a sliding air tight fit, the cover having an air release valve to allow escape of air from the container when the cover is pressed onto the container with the air release valve held open during the installation to release air from the container to create a vacuum seal with at least a partial vacuum in the container with the cover fully installed on the container with a tight vacuum seal fit and the cover only releasable for removal by opening the air release valve to admit air back into the container to break the vacuum seal and allow a user to slide the cover off with the air release valve held open.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Closed containers keep items fresher within the container with a vacuum or partial vacuum within the container so that there is less air in the container to cause contained items to spoil, thereby preventing or prolonging spoilage. Prior art containers fail to provide a simple vacuum closure with a sliding cover rather than a threaded cover and a simple air release valve rather than a vacuum pump.
The closest prior art of which applicants are aware is their prior U.S. Pat. No. 5,397,024 to Wu et al. The cover includes a valve depressible inward of the cover for allowing air to flow inward or outward of the cover. However, the valve assembly includes a screw secured to the plug rod and engaged with the cover for preventing the valve assembly from disengaging from the cover. The screw is normally made of metal and may not be easily threaded into place. In addition, the screw which is made of metal material may not closely enclose the opening of the cover such that a rubber ring and a gasket are required to be engaged on the screw for engaging with the cover so as to enclose the opening. Furthermore, the inner thread of the plug rod may be easily damaged by the metal screw. The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional covers for containers.
Another related prior art U.S. Pat. No. 5,697,510, issued Dec. 16, 1997 to Wang et al., provides a container including a cover engaged on an open top. A channel and an opening are formed in the cover. A knob is slidably engaged in the channel and includes a tube having a pair of shoulders. A plug has a pair of hooks engaged into the tube and engaged with the shoulders so as to secure the plug to the tube. A spring is biased between the knob and the plug for biasing the knob partially outward of the cover and for forcing the plug against the cover to enclose the orifice. The plug can be made of plastic material instead of metal material.
The prior art patents fail to provide a means for carrying the container or means for stacking a number of the containers or means for securely locking the cover on the container body.
What is needed is a cover fit precisely over a container with an air-tight sliding fit and an air release valve to create a vacuum seal fit with a vacuum or partial vacuum in the container by installing the cover thereon and a twist lock for the top with a top handle and adjacent air release valve to carry the container by the top handle.